[lnst] NetTestSlave: don't crash when deconfiguration fails

[olichtne]

commit 7986a213bc2a20dde3ccd30caab575442966f352
Author: Ondrej Lichtner <olichtne(a)redhat.com&gt;
Date:   Thu May 7 13:31:48 2015 +0200

    NetTestSlave: don't crash when deconfiguration fails
    
    Trying to deconfigure a device that wasn't configured causes lnst-slave
    to get into an inconsistent state. This patch fixes the issue by
    skipping the deconfiguration and logging an error message.
    
    Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;

 lnst/Slave/InterfaceManager.py |    2 +-
 lnst/Slave/NetTestSlave.py     |    5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/lnst/Slave/InterfaceManager.py b/lnst/Slave/InterfaceManager.py
index b2bb92e..5727646 100644
--- a/lnst/Slave/InterfaceManager.py
+++ b/lnst/Slave/InterfaceManager.py
@@ -132,7 +132,7 @@ class InterfaceManager(object):
         elif if_id in self._tmp_mapping:
             return self._tmp_mapping[if_id]
         else:
-            raise IfMgrError("No device with id %s mapped." % if_id)
+            return None
 
     def get_mapped_devices(self):
         ret = {}
diff --git a/lnst/Slave/NetTestSlave.py b/lnst/Slave/NetTestSlave.py
index 8eb1f99..ec6de85 100644
--- a/lnst/Slave/NetTestSlave.py
+++ b/lnst/Slave/NetTestSlave.py
@@ -253,7 +253,10 @@ class SlaveMethods:
 
     def deconfigure_interface(self, if_id):
         device = self._if_manager.get_mapped_device(if_id)
-        device.clear_configuration()
+        if device is not None:
+            device.clear_configuration()
+        else:
+            logging.error("No device with id '%s' to deconfigure." %
if_id)
         return True
 
     def start_packet_capture(self, filt):